『Flow meter program』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
1. Process for using electromagnetic flowmeter
The use of electromagnetic flowmeter requires strict adherence to the six step standardized process, including installation inspection, electrical connection caution, parameter setting, power on preheating, zero point calibration, and gradual valve opening, to ensure measurement accuracy. 1. Installation inspection direction verification: Confirm that the sensor arrow is consistent with the fluid direction, and prioritize the vertical installation and bottom-up full pipe flow scheme. Sealing test: Use pressure detection flange connection to ensure that the gasket compression meets the pipeline sealing standard and avoid medium leakage. Grounding treatment: The resistance value of the independent grounding electrode is ≤ 4 Ω. If it is directly connected to a metal pipeline, the three electrode grounding method should be used first.
2. Electrical connection inspection. Power verification: Check the voltage range indicated on the nameplate, and use a multimeter to confirm that the voltage fluctuation value of the connection is ≤ ± 10% of the rated voltage. Signal circuit: A twisted pair shielded cable is used to transmit 4-20mA signals, and the shielding layer is single ended to the grounding terminal block of the control cabinet. 3. Parameter configuration: Medium characteristics: input medium conductivity threshold (recommended ≥ 5 μ S/cm), fluid temperature, and pipeline material compensation coefficient. Range optimization: Set the upper limit of the range to 1.2-1.5 times the maximum process flow rate, and the lower limit is usually kept at 0m/s. 4. After powering on the initialization instrument, start a self check program for no less than 20 minutes, wai
2. PLC Accumulated Flow Program
The core implementation logic of PLC Accumulated Flow Program revolves around flow signal sampling, time interval calculation, and continuous accumulation. The following are three typical methods for analysis:
1. Preliminary Preparation 1 The hardware configuration connects the flow sensor to the analog input module of the PLC (such as Siemens SM 123-5AI), and receives the flow signal through the channel address (such as IV0.0). 2. The software is set to create a storage variable in the TIA Portal, such as "FlowAcc" for cumulative values, and the instantaneous flow variable corresponds to the sensor input address.
II. Method Comparison and Application Scenarios 1 Approximate integration method • Using time slicing calculation: Read the instantaneous flow rate every 100ms, multiply the average of two adjacent sampling values by the time interval (such as 0.1 seconds), and accumulate them in segments to the total amount. • Applicable scenarios: For pipeline systems with large flow fluctuations, the cumulative accuracy is improved through high-frequency sampling by Wild Rotten Zen
2. Encapsulate FB block method • Use modular programming: create a Totalizer function block in SCL language, define temporary variables to store intermediate values. • Call process: Run in a loop interrupt block (such as OB30) with a cycle of 100ms, and associate sensor inputs with cumulative variable noise levels through parameter interfaces. • Advantages: High code reusability, suitable for tedious projects of parallel accumulation of multiple flow meters
3. Conv
Hot Blog
Related AD
